1. Field of Invention
The present invention relates generally to an improved method of making probe needles for probe cards. More particularly, the present invention relates to the apparatus used in bending the probe needles for probe cards.
2. Description of Prior Art
Probe needles (or leads) used for probe card assembly are now bended and inspected manually. The probe needles are bent to the desired tip diameter and angle with a tool known as a jig. A trial and error method is used during the setup until the desired parameters are achieved. The inspection for the desired tip length, diameter and angle is done on a shadow comparator. Comparison is done by matching the shadow of the needle to a template.
Workers in the art are aware that this process is slow, tedious, and prone to human error. The human error and manual aspects of this process lead ultimately in not being able to use about 20 percent of probe pins.
Others have striven to solve this problem. For Example U.S. Pat. No. 5,513,430 (Yanof et al.) teaches creating the leads as part of the device and using resist and deposition to form the probe needles at appropriate angle. U.S. Pat. No. 4,892,122 (Ickes) teaches a probe pin alignment tool. U.S. Pat. No. 4,510,686 (Foster) teaches an apparatus for straightening and aligning leads. However this straightening and aligning takes place after the probe needles were bent. U.S. Pat. No. 5,969,533 (Takagi) shows a very general process of a probe card having bent probe tips. Finally, U.S. Pat. No. 5,517,126 (Yamaguchi) teaches a probe apparatus for testing.
Accordingly, the present invention provides a method for bending the probe needles that is semi-automated and uses machine vision to eliminate human error. Further to improve the output of the probes from approximately 1.5 minutes per probe to approximately 7.5 seconds per probe. Finally the devices that are unusable due to error in probe needles drops from approximately 20 percent to approximately 1 percent.
Another purpose of the present invention is to provide an apparatus for bending a probe pin having a base structure with a guide block attached to the top of the base structure. The structure further comprising a bending fixture for bending of a probe pin such that a probe pin can be placed on the guide block and pushed into place, and then bended by the bending fixture.